<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <h1>李二先生的web页面</h1>
    <p id="demo">在故乡的阿姀</p>
    <button id="btn" onclick="myFuntion()">点啊</button>
</body>
<script>
    // 获取时间
    // console.log(num);
    // function myFuntion(){
    //     document.write(Date())
    // }
    // var demo = document.getElementById('demo');
    // 改变元素的文本 innerHTML
    // demo.innerHTML = "不会知道李二先生在想她";
    // 窗口弹出
// window.alert(5 + 6);
var A = 10;
var B = 20;
console.log(A,B)

var C = A;
console.log(C);
var A = B;
console.log(A)
var B = C;
console.log(B); 
</script>
</html>